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Pickup from the office
Pickup from the office in Moscow
- If placed before 15:00 on a weekday, the order can be picked up after 17:00 on the same day, otherwise - on the next weekday after 17:00. We will call and confirm the readiness of the order.
- You can receive your order from 10:00 to 21:00 seven days a week after it is ready. Your order will be waiting for you within 3 working days. If you want to extend the shelf life, just write or call.
- Please note your order number before your visit. It is required upon receipt.
- To get to us, show your passport, say that you are in Amperka, and take the elevator to the 3rd floor.
- for free
Delivery by courier in Moscow
- We deliver the next day if you order before 20:00, otherwise - every other day.
- Couriers work from Monday to Saturday, from 10:00 to 22:00.
- You can pay for your order in cash upon receipt or online when placing your order.
- 250 ₽
Delivery to PickPoint
- PickPoint.
- You can pay for your order in cash upon receipt or online when placing your order.
- 240 ₽
Delivery by courier in St. Petersburg
Delivery by courier in St. Petersburg
- We deliver in a day if you order before 20:00, otherwise - in two days.
- Couriers work from Monday to Saturday, from 11:00 to 22:00.
- When agreeing on your order, you can select a three-hour delivery interval (the earliest is from 12:00 to 15:00).
- You can pay for your order in cash upon receipt or online when placing your order.
- 350 ₽
Delivery to PickPoint
- Delivery to a pick-up point is a modern, convenient and fast way to receive your order without calling or catching couriers.
- A pick-up point is a kiosk with a person or an array of iron boxes. They are placed in supermarkets, office centers and other popular places. Your order will arrive at the location you select.
- You can find your nearest location on the PickPoint map.
- Delivery time is from 1 to 8 days depending on the city. For example, in Moscow it is 1-2 days; in St. Petersburg - 2-3 days.
- When the order arrives at the pickup point, you will receive an SMS with a code to receive it.
- At any convenient time within three days, you can come to the point and receive your order using the code from SMS.
- You can pay for your order in cash upon receipt or online when placing your order.
- Delivery cost starts from 240 rubles depending on the city and size of the order. It is calculated automatically during checkout.
- 240 ₽
Delivery to pick-up point
Delivery to PickPoint
- Delivery to a pick-up point is a modern, convenient and fast way to receive your order without calling or catching couriers.
- A pick-up point is a kiosk with a person or an array of iron boxes. They are placed in supermarkets, office centers and other popular places. Your order will arrive at the location you select.
- You can find your nearest location on the PickPoint map.
- Delivery time is from 1 to 8 days depending on the city. For example, in Moscow it is 1-2 days; in St. Petersburg - 2-3 days.
- When the order arrives at the pickup point, you will receive an SMS with a code to receive it.
- At any convenient time within three days, you can come to the point and receive your order using the code from SMS.
- You can pay for your order in cash upon receipt or online when placing your order.
- Delivery cost starts from 240 rubles depending on the city and size of the order. It is calculated automatically during checkout.
Post office
- Delivery is carried out to the nearest post office departments in any locality Russia.
- The tariff and delivery time are dictated by Russian Post. On average, the waiting time is 2 weeks.
- We deliver the order to Russian Post within two working days.
- You can pay for your order in cash upon receipt (cash on delivery) or online when placing your order.
- The cost is calculated automatically during the order and should average about 400 rubles.
Delivery by EMS
- The EMS Russian Post service works faster and more reliably than regular mail and delivers to the door buyer.
- The tariff and delivery time are dictated by the EMS service. The average waiting time in Russia is 4-5 days.
- We transfer the order to EMS within two working days.
- You can only pay for your order online when placing your order.
- The cost is calculated automatically during checkout and should average 400-800 rubles for Russia and 1500-2000 rubles for CIS countries.
In addition to the online store, the product is also presented:
Office store, Taganskaya metro station
Office store, Taganskaya metro station
Items from the office cannot be ordered online or reserved. You can only come, grab and run. The available quantity is valid at the time the page is loaded.
The office is located a 5-minute walk from Taganskaya metro station, at Bolshoi Drovyanoy Lane, building 6.
Soon Shop-workshop, metro station Ligovsky Prospekt
Shop-workshop, metro station Ligovsky Prospekt
Items from the workshop store cannot be ordered online or reserved. You can only come, grab and run. The available quantity is valid at the time the page is loaded.
The store-workshop is located a three-minute walk from the Ligovsky Prospekt metro station, on the territory of the Loft Project Floors space, at 74D Ligovsky Prospekt.
The capacitive touch sensor works like a regular button, but there are no moving parts. The button will sense “pressure” through the body of the device and act as a contactless switch in home automation projects.
The sensor works through non-metallic materials - plastic, cardboard, plywood or glass. This feature can be used to create hidden or protected controls.
Place the module in a sealed case or hide it under the front panel of the device - the button will sense the approach of your finger even through a four-millimeter dielectric layer.
Use as a “button” is not the only use case for capacitive sensors. They are perfect for monitoring the water level in a plastic barrel or glass aquarium.
What's on board
The touch detection system consists of a sensing element, a unit for measuring the capacitance of the sensor and a logic circuit that responds to changes in capacitance when an object approaches.
A conductive circuit on the front of the module is used as a sensitive element.
The logic is based on the AT42QT1010 chip. It is responsible for automatic calibration of the sensor. Calibration takes approximately half a second and is performed immediately after power is supplied to the module. In addition, the microcircuit filters the values, compensates for the drift of the capacitive sensor and adjusts the operation of the device when the temperature and humidity of the environment changes.
Each time the sensor is triggered, a bright red LED lights up. This will help when debugging the project and will be useful for creating interactive control panels.
Connection
The touch module is essentially similar to a digital button. While the button is pressed, the sensor outputs a logical one; when the button is not pressed - logical zero.
In a simple version, the module is connected to the control electronics like a simple button - with one.
To do this, use the left group of contacts:
- Contact S is a signal pin connected to the digital input of the controller.
- Contact V - power. Connects to the 3.3-5 V power line.
- Contact G - connects to ground.
In the right group of contacts, only one pin is used - M. It switches the operating modes of the module. The two remaining legs are used to securely fix the module to the Troyka Slot Shield.
Switching operating mode
By default, the module operates in low power mode. The sensor is polled once every 80 milliseconds. This significantly saves battery energy.
If you need to increase the responsiveness of the interface, connect pin M to the controller and apply a logical one to it. The module will switch to high-speed data processing mode, the sensor polling interval will decrease to 10 milliseconds.
Equipment
- 1× Board module
Characteristics
- Supply voltage: 3.3-5 V
- Sensor controller: AT42QT1010
- Button interface: digital, binary
- Dimensions: 25×25 mm
Here we will consider sound and touch sensors, most often used as part of alarm systems.
Touch sensor module KY-036
The module is essentially a touch button. As the author understands, the operating principle of the device is based on the fact that by touching the contact of the sensor, a person becomes an antenna for receiving interference at the frequency of a household AC network. These signals are sent to the comparator LM393YD
The module dimensions are 42 x 15 x 13 mm, weight 2.8 g, the module board has a mounting hole with a diameter of 3 mm. Power is indicated by LED L1.
When the sensor is triggered, LED L2 lights up (flashes). Current consumption is 3.9 mA in standby mode and 4.9 mA when triggered.
It is not entirely clear what sensitivity threshold of the sensor should be regulated by a variable resistor. These modules with the LM393YD comparator are standard and various sensors are soldered to them, thus obtaining modules for various purposes. Power terminals “G” – common wire, “+” – +5V power supply. There is a low logic level at the digital input “D0”; when the sensor is triggered, pulses with a frequency of 50 Hz appear at the output. At pin “A0” there is a signal inverted relative to “D0”. In general, the module works discretely, like a button, which can be verified using the LED_with_button program.
The touch sensor allows you to use any metal surface as a control button; the absence of moving parts should have a positive effect on durability and reliability.
Sound sensor module KY-037
The module must be triggered by sounds whose volume exceeds a specified limit. The sensitive element of the module is a microphone that works together with a comparator on the LM393YD chip.
The module dimensions are 42 x 15 x 13 mm, weight 3.4 g, similar to the previous case, the module board has a mounting hole with a diameter of 3 mm. Power is indicated by LED L1. Power terminals “G” – common wire, “+” – +5V power supply.
Current consumption is 4.1 mA in standby mode and 5 mA when triggered.
At pin “A0” the voltage changes in accordance with the volume level of the signals received by the microphone; as the volume increases, the readings decrease, this can be verified using the AnalogInput2 program.
There is a low logic level at the digital input “D0”; when the specified threshold is exceeded, the low level changes to high. The response threshold can be adjusted with a variable resistor. In this case, LED L2 lights up. With a sharp loud sound, there is a delay of 1-2 s when switching back.
Overall, a useful sensor for organizing a smart home or alarm system.
Sound sensor module KY-038
At first glance, the module seems similar to the previous one. The sensitive element of the module is the microphone; it should be noted that there is not much information on this module on the network.
The module dimensions are 40 x 15 x 13 mm, weight 2.8 g, similar to the previous case, the module board has a mounting hole with a diameter of 3 mm. Power is indicated by LED L1. Power terminals “G” – common wire, “+” – +5V power supply.
When the reed switch is activated, LED L2 lights up. Current consumption is 4.2 mA in standby mode and up to 6 mA when triggered.
At pin “A0”, when the volume level increases, the readings increase (the AnalogInput2 program was used).
There is a low logic level at pin “D0”; when the sensor is triggered, it changes to high. The response threshold is adjusted using a trimming resistor (using the LED_with_button program).
This sensor really is practically no different from the previous one, but their interchangeability is not always possible, because When the volume level changes, the nature of the level change causes the voltage at the analog output to differ.
conclusions
This concludes the review of a large set of various sensors for the Arduino hardware platform. In general, this set made a mixed impression on the author. The set includes both quite complex sensors and very simple designs. And if, if there are current-limiting resistors, LED indicators, etc. on the board, the author is ready to admit the usefulness of such modules, then a small part of the modules is a single radio element on the board. Why such modules are needed remains unclear (apparently, mounting on standard boards serves the purpose of unification). Overall, the kit is a good way to get acquainted with most of the common sensors used in Arduino projects.
useful links
- http://arduino-kit.ru/catalog/id/modul-datchika-kasaniya
- http://www.zi-zi.ru/module/module-ky036
- http://robocraft.ru/blog/arduino/57.html
- http://arduino-kit.ru/catalog/id/modul-datchika-zvuka
- http://www.zi-zi.ru/module/module-ky037
- http://arduino-kit.ru/catalog/id/modul-datchika-zvuka_
- http://smart-boards.ml/module-audiovideo-4.php
In this article, we'll take a close (but not too deep) look at the principles of electricity that allow us to detect the touch of a human finger using little more than just a capacitor.
Capacitors can be touch sensitive
Over the past decade or so, it has become truly difficult to imagine a world with electronics without touch sensors. Smartphones are the most visible and widespread example of this, but of course there are numerous other devices and systems that have touch sensors. Both capacitance and resistance can be used to build touch sensors; in this article we will discuss only capacitive sensors, which are more preferable in implementation.
Although applications based on capacitive sensors can be quite complex, the fundamental principles behind the technology are quite simple. In fact, if you understand the concept of capacitance and the factors that determine the capacitance of a particular capacitor, you are on the right track in understanding the workings of capacitive touch sensors.
Capacitive touch sensors fall into two main categories: mutual capacitance-based and self-capacitance-based. The first of these, in which the sensor capacitor consists of two terminals that act as emitting and receiving electrodes, is more preferable for touch displays. The latter, in which one terminal of the sensor capacitor is connected to ground, is a direct approach that is suitable for a touch button, slider or wheel. In this article we will look at sensors based on intrinsic capacitance.
PCB based capacitor
Capacitors can be of various types. We're all used to seeing capacitance in the form of leaded components or surface mount packages, but in reality, all you really need are two conductors separated by an insulating material (i.e. dielectric). Thus, it is quite simple to create a capacitor using only electrically conductive layers separated by a printed circuit board. For example, consider the following top view and side view of a printed circuit capacitor being used as a touch touch button (note the transition to another PCB layer in the side view illustration).
The insulating separation between the touch button and the surrounding copper is created by a capacitor. In this case, the surrounding copper is connected to ground, and hence our touch button can be modeled as a capacitor between the touch signal pad and ground.
Now you might want to know how much capacitance this PCB layout actually provides. Moreover, how do we calculate it accurately? The answer to the first question is that the capacitance is very small, maybe around 10 pF. Regarding the second question: don't worry if you forgot the electrostatics because the exact value of the capacitance of the capacitor does not matter. We are only looking for changes in capacitance, and we can detect these changes without knowing the capacitance rating of the printed capacitor.
Finger influence
So what is causing these capacitance changes that the touch sensor controller is going to detect? Well, of course, a human finger.
Before we discuss why the finger changes capacitance, it is important to understand that there is no direct electrical contact; the finger is insulated from the capacitor by varnish on the printed circuit board and, as a rule, by a layer of plastic that separates the device's electronics from the external environment. So the finger does not discharge the capacitor, and furthermore, the amount of charge stored in a capacitor at a certain moment is not of interest - rather, the capacitance at a certain moment is of interest.
So why does the presence of a finger change the capacitance? There are two reasons: the first involves the dielectric properties of the finger, and the second involves its conductive properties.
Finger is like a dielectric
We usually think of a capacitor as having a fixed value, determined by the area of the two conducting plates, the distance between them, and the dielectric constant of the material between the plates. We, of course, cannot change the physical dimensions of the capacitor simply by touching it, but we Can change the dielectric constant, since the human finger has dielectric characteristics that differ from the material (presumably air) it displaces. It is true that the finger will not be in the actual dielectric region, i.e. in the insulating space directly between the conductors, but such “invasion” into the capacitor is not necessary:
As shown in the figure, to change the dielectric characteristics, there is no need to place a finger between the plates, since the electric field of the capacitor spreads to the surrounding environment.
It turns out that human flesh is a pretty good dielectric because our bodies are made mostly of water. The relative dielectric constant of a vacuum is 1, and the relative dielectric constant of air is only slightly higher (about 1.0006 at sea level at room temperature). The relative permittivity of water is much higher, around 80. Thus, the interaction of the finger with the electric field of the capacitor represents an increase in the relative permittivity, and therefore results in an increase in capacitance.
Finger as a guide
Anyone who has experienced an electric shock knows that human skin conducts electricity. I already mentioned above that there is no direct contact between the finger and the touch button (that is, the situation when the finger discharges the printed capacitor). However, this does not mean that finger conductivity is not important. It is actually quite important, since the finger becomes the second conductive plate in the additional capacitor:
In practice, we can assume that this new finger capacitor is connected in parallel with the existing printed capacitor. This situation is a little more complicated because the person using the sensing device is not electrically connected to ground on the circuit board, and thus the two capacitors are not connected in parallel in the usual circuit analysis sense.
However, we can think of the human body as providing virtual ground because it has a relatively large capacity to absorb electrical charge. In any case, we don't need to worry about the exact electrical connection between the finger capacitor and the printed capacitor; The important point is that connecting these two capacitors in pseudo-parallel means that the finger will increase the total capacitance as the capacitor is added in parallel.
Thus, we can see that both influence mechanisms between the finger and the capacitive touch sensor contribute to the increase in capacitance.
Close distance or contact
The previous discussion leads us to an interesting feature of capacitive touch sensors: the measured change in capacitance can be caused not only by contact between the finger and the sensor, but also close distance between them. I usually think of a touch device as replacing a mechanical switch or button, but capacitive touch sensor technology actually introduces a new level of functionality by allowing the system to sense the distance between the sensor and your finger.
Both capacitance changing mechanisms described above have an effect that depends on distance. For a dielectric constant-based mechanism, the amount of "meat" dielectric interaction with the capacitor's electric field increases as your finger approaches the conductive parts of the printed capacitor. For a conductive mechanism, the capacitance of a finger capacitor (like any other capacitor) is inversely proportional to the distance between the conductive plates.
Touch sensor for Arduino
The module is a touch button; a digital signal is generated at its output, the voltage of which corresponds to the levels of logical one and zero. Refers to capacitive touch sensors. We encounter this kind of data input devices when working with the display of a tablet, iPhone or touchscreen monitor. If on the monitor we click on an icon with a stylus or finger, then here we use an area of the board surface the size of a Windows icon, touching it only with a finger, the stylus is excluded. The basis of the module is the TTP223-BA6 chip. There is a power indicator.
Controlling the rhythm of melody playback
When installed in the device, the touch area of the surface of the module board is covered with a thin layer of fiberglass, plastic, glass or wood. The advantages of a capacitive touch button include a long service life, the ability to seal the front panel of the device, and anti-vandal properties. This allows the touch sensor to be used in devices operating outdoors in conditions of direct contact with water droplets. For example, a doorbell button or household appliances. An interesting application in smart home equipment is replacing light switches.
Characteristics
Supply voltage 2.5 - 5.5 V
Touch response time in various current consumption modes
low 220 ms
normal 60 ms
Output signal
Voltage
high log. level 0.8 X supply voltage
low log level 0.3 X supply voltage
Current at 3 V supply and logical levels, mA
low 8
high -4
Board dimensions 28 x 24 x 8 mm
Contacts and signal
No touch - the output signal has a low logical level, touch - the sensor output is logical one.
Why does it work or a little theory
The human body, like everything around us, has electrical characteristics. When a touch sensor is triggered, our capacitance, resistance, and inductance appear. On the bottom side of the module board there is a section of foil connected to the input of the microcircuit. Between the operator's finger and the foil on the bottom side there is a layer of dielectric - the material of the supporting base of the module's printed circuit board. At the moment of contact, the human body is charged with a microscopic current flowing through a capacitor formed by a section of foil and a person’s finger. In a simplified view, current flows through two series-connected capacitors: foil, a finger located on opposite surfaces of the board, and the human body. Therefore, if the surface of the board is covered with a thin layer of insulator, this will lead to an increase in the thickness of the dielectric layer of the foil-finger capacitor and will not disrupt the operation of the module.
The TTP223-BA6 microcircuit detects an insignificant microcurrent pulse and registers a touch. Due to the properties of the microcircuit, working with such currents does not cause any harm. When we touch the body of a working TV or monitor, microcurrents of greater magnitude pass through us.
Low consumption mode
After power is applied, the touch sensor is in low power mode. After triggering for 12 seconds, the module goes into normal mode. If no further contact occurs, the module will return to low current consumption mode. The speed of the module's response to touch in various modes is given in the characteristics above.
Working together with Arduino UNO
Load the following program into the Arduino UNO.
#define ctsPin 2 // Contact for connecting the touch sensor signal line
int ledPin = 13; // Contact for LED
Void setup() (
Serial.begin(9600);
pinMode(ledPin, OUTPUT);
pinMode(ctsPin, INPUT);
}
Void loop() (
int ctsValue = digitalRead(ctsPin);
if (ctsValue == HIGH)(
digitalWrite(ledPin, HIGH);
Serial.println("TOUCHED");
}
else(
digitalWrite(ledPin,LOW);
Serial.println("not touched");
}
delay(500);
}
Connect the touch sensor and Arduino UNO as shown in the figure. The circuit can be supplemented with an LED that turns on when the sensor is touched, connected through a 430 Ohm resistor to pin 13. Touch buttons are often equipped with a touch indicator. This makes it more convenient for the operator to work. When we press a mechanical button, we feel a click regardless of the reaction of the system. Here the novelty of the technology is a little surprising because of our motor skills that have developed over the years. The pressure indicator saves us from an excessive feeling of novelty.
For some electrical devices, there is a need for touch activation, that is, the start or end of operation must occur with a simple touch of a finger to the touch contact. This can be used in circuits of electronic locks, alarms, and ordinary equipment, which simplifies its activation and deactivation (you just need to touch it).
In this article I propose a fairly simple electronic circuit for a touch switch that can be assembled by almost anyone. This circuit consists of only a few electronic components, the main ones of which are bipolar transistors, which act as signal amplifiers. The sensor wire itself (which needs to be touched) is connected to the input (base) of the first transistor. The output of the transistor produces a signal amplified hundreds of times, which is fed to the next element. The second transistor amplifies the previously amplified signal even more, and the third stage of the circuit does the same. As a result, from an extremely small signal coming from the sensor, we obtain a current that can light an LED (or turn on a relay that will control one or another device).
Let me remind you that a bipolar transistor is a semiconductor element that has three terminals (emitter, collector and base). It is capable of amplifying the electrical signal by 10-1000 times. When a small signal (somewhere from 0.6 to 0.7 volts) is applied to the control pin, we can obtain an electric current and/or voltage of a much larger value at the output.
The base is the control electrode relative to the emitter. That is, a certain voltage is supplied from the power source to the base (through a limiting resistor creating a certain bias) and the collector. When the voltage between the base and emitter is up to 0.6 volts, the transistor will still be closed (it will not pass current through itself relative to the emitter and collector). By increasing the voltage between the base and emitter from 0.6 to somewhere up to 0.7 volts, we gradually open the transistor from a completely closed state to a completely open state. Consequently, the transistor plays the role of a variable resistor, which is controlled by small currents and can change its resistance from infinitely large to practically zero (it still exists, albeit very small).
Resistors in the circuit of a simple touch switch, located in the collector circuit, act as current limiters. Their ratings are 1 megaohm, 1 kiloohm and 220 ohm. You can install small power, small in size (the currents in the circuit are quite small). This electrical circuit uses bipolar transistors of the KT315 type (suitable with any letter index). These transistors are old-fashioned, you can find them anywhere, and they cost pennies (if you buy them). You can replace them with KT3102 or any others with similar characteristics. These transistors have n-p-n conductivity (beginners should take this into account). You can put transistors and reverse conductivity (pnp) of the KT361 or KT3107 series into the circuit, but then you will need to change the polarity on the power supply (connect minus to plus and vice versa).
I would like to note that this electrical circuit of the sensor is not fixed, that is, the output device will be triggered and work only when you touch the input sensor. As soon as you stop touching the sensor, the output device will also turn off.
Initially, in the circuit of a simple touch switch, I installed a regular LED at the output, which simply lit up when the sensor was touched. If you put a small relay instead of an LED, then you can already have a switch at the output of the circuit, which can be connected to various electrical devices (bell, light bulb, motor, etc.). In parallel with the relay coil, you will need to solder an electrolytic capacitor of small capacity (somewhere from 100 to 1000 microfarads, and with a voltage no less than that of the power source). And also connect a diode (reverse connection), which will eliminate the influence of self-induction voltage occurring on the relay coils on the circuit itself. Any diode will do!
P.S. Please note that the LED has polarity! If you place it incorrectly, it will not light up. If using a relay, consider the output current of the transistor. That is, KT315 can have a current of no more than 100 milliamps at its output. Consequently, if you install a large switch whose coil consumes large currents, the transistor may fail. You need to install a relay with the appropriate current on the coil or install a more powerful bipolar transistor at the output of the circuit.